Suction amplifier



Sept 26, 1961 H. HURvl-rz 3,001,539

sUcTIoN AMPLIFIER FiledAug. 15, 1960 INVENTOR HYMAN HUH VITZ ATTORNEY SUCTION AMPLIFIER Hyman Hurvitz, 1313 Juniper St. NW., s Washington, D.C. Filed Aug. 1S, 1960, Ser. No. 49,752 Y 2 1 Claims. (Cl. 1371-83) The present inventionrrelates generally to fluid ampliflersof the type which utilize no moving parts, and more particularly to fluid amplifiers which utilize differential; pressure against the side of an elongated main fluid stream offluid to control the direction of the stream Fluid amplifiers having no moving parts except the tiuid itself are Well known-in the prior art. Such ampli-` fiers are of various types.l O ne such type is known as the stream interaction or momentum interchange type, I n such an amplier a power nozzle is supplied with pressurized iiuid and issues a powerjet Srrstreatrn,v c ,ontrol nozzle directs fluid against the side of the power j et and dellects the power jet- 4awayrffrom-the control nozzle. Momentum is conserved in the system and the power je'twill thereforeV ow atan angle withfrespect; to; its' original directinsch that thetangentlofwthis; angle is a` functionof the'inomentum of the control stre'a-m'and the momentum of thepower stream.l it is thus possible to direct a'highupoweredjet Atowardfor away from a target area in response toafcontrol stream of lowerpower. f j f fl' `A further type of uid yplifie'r'l is `kncf wr1masjthe boundary layer liuid amplifier. Boundary. layer fluid amplifiers direct high energy powerfjet's directly'towarda t`a'r'gi'.=,t area or' receiving tube system',4 by .pressure distribution in a power jet bondary'lay'er region. This'p'res sure-distribution is controlledY by the"wallcon'guration ofen interaction chamberrie., a cl'ian'iber inwhich the power j'et andcontroltjetsinteract, aswell. as by power .jetje'nergy level, fluid A'transport effects', back-loading 'of the"amplier outputs, and the 'flow of control liuid through the power jet boundary layerIregio'n'. In a boundary layer control' iluid amplier'having two side walls on either side of a .power jet, 'special design of the interaction chamber configuration 'assures that the'povver j et will lock on to `one side wall, and remain in lock-on configuration even Without control fluid flow. When the povver jet isV suitablydeflccted towardjon'e side Wall'by Y3,001,539 :Patented Sept. 26, 1961-;

along the path of uid flow. The controlled exhaustion port then replaces the boundary layer region, havinga similar eifectin that it introduces a region of low` pressure adjacent to one side of the power stream. Egress-of iluid may be controlled either in. response to electrical' signals, ,-as by means of electro-fluid resistances, orby means of flapper valves. l The present invention alsoconcerns itself with a'modi-" cation of the momentum interchange amplifier, in .which iluid from the main stream is controllably evacuated through egress control" passages to create a transversepressure gradient across-the stream. Control of the trans-V versepressure gradient is effected either by flapper valves orelec-tro-fluid resistances, whereby any necessity for momentum interchange in response to a control jet is eliminated, the pressure adjacent to the main jet itself being utilized to control the activity of themain jet whenA a low pressure region is created on one or the .other'sidel ofthe main jet. i; Itis accordingly a broad Aobject of the present inven#V tion to provide novel types of fluid ampliers requiring' no moving parts. It is another object of the invention to provide a systenr of f iuid amplificationemploying controlled boundary layer effects, wherein the boundary layer pressures are' a"'control fluid jet it can lock onto thatsidewall andfr'e I f main in that locked on configuration even. after flow ofthei control fluid is' terminatedf; The Vunit thus'lp'ossessf. inherent' positive feed-back by virtue of the lockon conigurationof the interaction'chamber, andthe feed-back path is created and destroyed' in accordance With`the position of the power jet. In essence this implies'that power jets of prior art vdevices may be deflected -to one side or'the other sideo-f the interaction chamber in response to a pulse of control jet' pressure, vand having been so' deflected will remainjn' deflected position, by virtue of boundary layer lock"on,`u'ntil that position is disturbed by the application of sutcent pressure. to an appropriate control jet whichov'ercomes the lockon and d eects the powery jet towardV the other side of the chamber.

The present inventionconcerns itself with a typeof fluid amplifier utilizing no moving parts, in which bound-1 ary layer lock-on effects are employed bycontrolled reduction of pressure inl av boundary layer lock-on, region,l rather than by a control jet, this reduction being effected' by means of a channel communicating between the bound` ary layer interaction region; and a' region of lower pressure reduced belowthat whichis Vinduced by the fluid stream' itselfl. j y

It anot er` object ofthe invention to provide quasi-.1 boundary layerj control systems, in which low -pressures .A heretofore generated by boundary'layer effects are intro-L ducedby fluid egress passages having controllable rei sistance. -v .f Another object of the inventiqnresidesin the provision: of a systemfor controlling the direction of flow of a main Vliuid'stream byproviding controlled egressof iluid to afrgion .of relatively low pressure, the controlled egress occurring transversely of the direction of the main.` stream." A Y Still another object` of 'the invention is lto provide anovel 'system for controlling, fluid flow in response to dapper valves wherein the control effects of the flapperI valves are amplified.

Anothei object of the invention is to provide areplacement for a apper valve control system, whereinthe eiect of a tlapper valve is attained by means of an electro fluid resistance.

. The above and still further objects, features and acl-..3

vantages of' the present invention will become apparent upon consideration `of the following detailed description of one specific Yembodiment thereof, especially when taken in conjunction with the accompanying drawings, wherein:

` FIGURE 1 is a diagrammatic showing of a boundary.- layer liuid amplifier employing a nozzle valve controlled l egress passage vcommunicating with av boundary layerl control region; FIGURE 2 is a modification ofthe system of FIGURE 1 wherein the dapper valve of the system of FIGURE l is replaced by an electro-fluid resistance;

, FIGURE 3 is a schematic representation of a fluid e amplifier employing double ilapper valves to control the pressure in boundary layer control regions; FIGURE 4 is a modification of the system ofFlGURE- 3' wherein specially shaped boundary layer Vregionsare dispensed with; and

fr 'FIGURE 5 is a modification of the system of FIGURE 4 wherein the flapper valves of FIGURE 4 are replaced by electro-fluid -resistances Referring now more particularly to the accompanying I drawings, vthe reference numeral 1 denotes a pump which ejects gas (or other fluid) in the direction of effect at one of the offsets 36a, 36b may be caused topreorle output control channels, perse, when these areV permitted tol exit into a region of low ambient pressure.

FIGURE is a modification of FIGURE 4 wherein the iiap valve controlchannels .are replaced by iluid resistances of the electrically responsive type, the two systems being otherwise identical.

defined in the appended claims. i.

l.. A fluid device, comprising a passage, an 4olset in a wall of said passage arranged to provideareduced Huid-pressure offset region in response to ow-of iluid along .said passage, a control channel communicting' with said offset region, said control channel com'rnunicatf ing with -a region of lower ambient pressurethan--i's` present in said olset region, and a variable'uid'resistparting fromthe true 'spirit and scopefof the' invention ance in series with said control channel. L l 2. The combination` according to claim -1 wherein-said" variable lluid resistance includes -a appervalve.

3. The combination according to claim l wherein saidvariable iluid yresistance includes an electrical fluid rc#L sistance.

The system of FIGURE 1 can permit some degree of l proportional flow as between the channels 3 and 4, li.e. it does not require that the stream iiow in one of the channels only. Complete transfer and lock-on of the stream into channel 4 occurs suddenly, however, when the nozzle 18 is sufficiently uncovered, the action being analogous to that ocurring in an electronic iiip-op. Once complete lock-on has occurred, a slight movement of the apper valve 17 toward the nozzle 18 will not be suicient to remove the lock-on, since the latter is in part due to the motion of fluid in the channel 4. The system therefore tends to be stable, i.e. once lock-on has occurred within the channel 4, that lock-on tends to remain until the apper valve 17 has moved to a position closer to the nozzle 18 than was the case when lock-on set in. Oscillation or instability of the system is thus prevented. What is true, in this respect, of the system of FIGURE l is likewise true of the system of FIGURE 2.

The basis for this capability is that the channel 3 is in direct line with the pump 1 so that fluid iiow due to the kinetic energy of the fluid always tends to takeplace in channel 3, except insofar as a sutlciently powerful diverting force exists. The system tends to be monostable toward channel 3. In the system of FIGURE 3, bistable operation exist, since whenever the stream becomes stronger in one or the other of the channels, the stream itself provides a positive feed-back due to boundary layer action, andflips the direction of the stream completely into that stream wherein flow predominates. While FIGURE 3 provides a boundary layer configuration in terms of the presence of lock-on off-sets to produce lock-on, the system of FIGURE 4 is essentially diierent -frorn that of FIGURE 3, in principle, because the system of FIGURE 4 does not utilize offsets. The system of vFIGURE 4 is essentially a momentum interchange unit, high pressure on one side of the jet being created statically byrload L and low pressure on the other side by a controlled passage leading to a regio-n of low pressure. A pressure gradient thus exists transversely of the jet, whichtends to cause a transverse flow of iluid across the jet, and thus to deflect the jet.

Momentum interchange, as described in the last preceding paragraph, is present in the embodiments of my invention illustrated in FIGURES l-S, inclusive, but in FIGURES 1 3 boundary layer effects are also introduced, and the transverse pressure gradient region terminates in one or more boundary layer regions, pressure in which is directly controlled, as by a llapper valve.

While I have described and illustrated one specific embodiment of my invention, it will be clear that variations of the details of construction which are specifically illustrated and described may be resorted to without de- `4.. The combination according to claim l wherein isf further provided a negative feed-back path Ibetween said passage and said olset region. Y f v 5. A duid device, comprising a first passage, a second passage, said passages having a-junction, va-sour 1oifl fluid under pressure communicating with said junction andinormally directing fluid preponderantly toward one of said passages, the other of said passages having a conguration including a recess arranged to provide a region of low pressure, whereby said fluid has a tendency to flow in said second passage, and means for controlling said low pressure, said means for controlling including a iiuid egress passage communicating with said recess.

6. The combination according to claim 5 wherein said tluid egress passage communicates with a region of relatively low ambient pressure, and wherein said means for controlling includes a ilapper valve.

7. The combination according to claim 5 wherein said uid control passage communicates with a region of relatively low ambient pressure, and wherein said means for controlling includes an electro-duid valve.

8. A iiuid operated device comprising a source of a stream of fluid, a reception region for said stream of tluid, means for reducing static pressure on one side of said stream, said means comprising an egress control passage for said fluid, said stream being detiectable toward said one side in `response to a reduction of static pressure on said one side due to egress of liuid through said egress' control passage.

9. A Huid operated device comprising a power nozzle, a source of l'luid under pressure connected to said power nozzle, a pair of passages having origins adjacent said power nozzle, said fluid being ejected by said power nozzle in a stream directed generally in the direction of said origins, and means for relatively controlling flow of said stream differentially to said origins, said last means comprising fluid control passageways communicating with said stream on opposite sides thereof, said'uid control passageways communicating with a region of static pressure lower than the static pressure in said stream adjacent said control passageways.

l0. The combination according to claim 9 wherein is provided an interaction chamber located between said powernozzle and said origins, said control passageways communicating with said interaction chamber.

ll. The combination according to claim 9 wherein said power nozzle is arranged normally to direct said iiuid equally toward said origins.

l2. The combination according to claim 9 wherein said power nozzle is arranged normally to direct said fluid into one of said origins only.

13. The combination according to claim l2 wherein is provided a controllable iluid resistance in at least one of said passageways.

14. A lluid operated device comprising apower nozzle for generating a iiuid stream, a source of fluid f under pressure connected with said power nozzle, a pair of passages having origins adjacent to said power nozzle, said stream being diverted by said power nozzle emmen# AS15'. The combination Yaccording to claim 14 wherein isjirovidei Vbmndary control -devices nfor reducing pres sureon'one -side -of -saidstream in response to ow of said-stream. 116;Thecombinationlaccording to claim 14 wherein said 'last' means includes va flappervalve for controlling slid, control massage,

I 17. The combination according to claim 14 wherein Y said: Lastjrneans lincludes an electro-'fluid `resistance forV vcont-rollingeigxessof--fluiciefrorn said control passage.

' 18. A uid operated device comprising a source of a stream o.f .uid, a receptionregion for said stream of uid, means for `reducingpressure on `one side of said stream, said means comprising'an egress control-passage for said `uifi, 'sadstream being 'deiioctable in response to-arednction of .pressure onsaid one vside due Ito egressv of uid, Athrough said egress control passage.

1129. me 'ne-earning@ ferai@ :is

iuio extending, transversely of saidv lastnamed of "fluid'sand in communication with said ,last-nanfrerlfV streanrof uid, and a variablefuid resi-staller:'eontrolllis;-

21. The combination Eaccording 'to 'claim '20 wlex-einf said uidlresistance inclides'a movable solid object located "No references eiterL 

